Can Alcohol Impair Muscle Growth?

You’re likely to see a lot of them at the gym: people “working on their gains,” as they like to say, by which they mean trying to build up their muscles and tone their body.  

All sorts of factors go into helping us grow our muscles, from putting them under enough resistance to eating enough protein. Hydration is another key element, as our muscles need water to help them function optimally. But where does alcohol fit into the mix? How does it affect our muscles? Let’s dive in.

What It Takes To Build Muscle

Before we look at alcohol's effect on muscle growth, it’s helpful to understand how we build muscles in the first place. Our muscle tissue is in a constant state of building up and breaking down. When we exercise, our muscles undergo stress and become damaged. To repair this damage, our muscles need protein. Muscle protein synthesis (MPS) is a process that promotes protein turnover and allows us to build muscle.

When muscle protein synthesis occurs at a faster rate than protein breakdown, muscle can grow. So the key to building muscle is to increase the rate of protein deposition while minimizing the rate of protein breakdown.

Certain hormones, such as testosterone, human growth hormone, and insulin growth factor, also play a role in muscle growth and repair. These hormones improve how the body processes proteins and stimulate anabolic hormones, which promote muscle growth and protein synthesis.

Various factors — including our genetics, age, gender, and our level of exercise —affect how rapidly we develop muscle. While cardiovascular activity can be beneficial, the best type of exercise to build muscle is strength training, such as lifting weights or using resistance bands.

Alcohol Disrupts Protein Synthesis

Research indicates that alcohol can impair muscle protein synthesis (MPS). Even when we consume optimal protein sources for muscle growth, alcohol can still negatively affect this process.

One study illustrates this well: it focused on eight physically active men performing weight lifting and interval training. They consumed whey protein and alcohol immediately after exercise and again four hours later. They also consumed a carbohydrate-rich meal two hours after training. Muscle biopsies were taken at two and eight hours following physical training, showing reduced rates of MPS.

Alcohol consumed with protein reduced MPS by 24% and 37% when combined with carbohydrates. Even though there was a partial rescue of MPS when protein was consumed, alcohol still negatively affected it. In other words, alcohol contributes to protein breakdown more than our nutrition does to protein synthesis. Alcohol is more detrimental than protein is good; we cannot make up for alcohol’s harm through good nutrition.

More specifically, alcohol seems to affect the activation and translation of many different signals involved in the protein synthesis process. Studies have shown that mTOR activation — which is associated with protein synthesis — is greatly reduced with alcohol intake. Reducing mTOR activity impairs protein synthesis and overall muscle gains.

Studies also show that alcohol consumption can decrease the activation of an important protein signaler — called p70S6K — that we need for protein synthesis.

Furthermore, alcohol seems to impair protein synthesis in males more than females. One study found that several shots of vodka right after a workout decreased muscle growth signaling in males, but not in females.

Alcohol Affects Hormones Important for Muscle Growth

Heavy alcohol consumption also leads to an imbalance in hormone production, which can affect our muscle building process. For instance, studies show that alcohol consumption after a workout can prolong the amount of time that cortisol — the stress hormone — is elevated in our blood. High levels of cortisol for an extended period of time is associated with muscle loss. Interestingly, research indicates that reducing our overall stress levels may help us build muscle.

Similarly, some studies have shown that elevated alcohol consumption converts testosterone into estrogen, which can be particularly problematic since testosterone is important for protein synthesis and muscle growth. Alcohol also decreases human growth hormone, which has negative effects on blood sugar maintenance and metabolism of muscles, bones, and our brain.

Furthermore, alcohol has been shown to induce insulin resistance. Insulin is important for muscle growth and is responsible for the absorption of carbohydrates into muscles. With limited absorption ability, muscle growth and recovery are impaired.

Alcohol Inhibits Muscle Recovery

It might sound odd, but rest and recovery are an important part of building muscle. Without adequate rest, our muscles won’t be able to efficiently repair themselves.

Sleep is particularly important for muscle recovery and tissue repair. Alcohol can disrupt our sleep cycle and prevent us from entering into rapid eye movement (REM) sleep, which is vital for our body’s restoration. Some research suggests that inadequate sleep contributes to the loss of muscle mass and inhibits muscle recovery, though more research is needed to confirm this link.

Furthermore, staying hydrated is vital for muscle growth and recovery, as it helps flush toxins and deliver essential nutrients to cells. Consuming alcohol after exercise — even just a beer with 4% alcohol — has been shown to negatively affect rehydration efforts.

The Bottom Line

So, can alcohol impair muscle growth? Yes! It’s proven to disrupt muscle protein synthesis, a process essential for building muscle. But alcohol can also weaken muscle growth by altering our hormonal balance and inhibiting our recovery efforts. So if you’re used to reaching for a cold beer after a workout, you might want to think again.

And if you’re trying to get healthier by limiting your alcohol consumption, Reframe can help. We’ve helped millions of people cut back on alcohol use and become the healthiest, strongest version of themselves.